AT&T is investigating the leak of personal data of 73 million account holders in the United States

New York (CNN) — AT&T has launched an investigation into the origin of a data breach that involved the personal information of 73 million current and former customers in the United States.

In a press release Saturday morning, the telecom giant said the data was “published on the dark web approximately two weeks ago” and includes information such as account holders’ Social Security numbers.

“It is not yet known whether the data…came from AT&T or any of its providers,” the company said. “AT&T currently has no evidence of unauthorized access to its systems that resulted in the exfiltration of the data set.”

The data appears to be from 2019 or earlier. According to AT&T, the leak does not include financial information or specific details about call history. The company said the breach revealed that approximately 7.6 million current account holders and 65.4 million former account holders were affected.

AT&T said it is contacting customers and asking them to reset their account passwords. It also urges customers to be alert to changes in their accounts or credit reports, saying that AT&T “will provide credit monitoring at our expense when appropriate.”

The company was alerted about the possible leak about two weeks ago. News of the leak was first posted on March 17 by X account VX-Underground.

At the time, AT&T told CNN: “We have no indication that our systems have been compromised. In 2021 we determined that the information provided in this online forum did not originate from our systems. “We believe and are working to confirm that the data set discussed today is the same data set that has been recycled multiple times on this platform.”